This invention relates to hanger bars for supporting fixtures from the ceiling of a room, or the like, and more particularly to an improved such hanger bar, which is adapted to be adjustably and securely mounted between ceiling joists to provide a sturdier support for ceiling fixtures, such as lamps, ceiling fans, and the like.
It has long been customary to employ so-called hanger bars for supporting rather heavy electrical fixtures from the ceiling of a room or the like. Most such fixtures, particularly if they happen to be rather heavy, cannot be be attached directly to the ceiling of a room, because most ceilings simply are not sturdy enough to support a heavy load. If, of course, it is desired to position a ceiling fixture at a particular point in a room in which the fixture would register vertically with an existing ceiling joist, then the fixture could be fastened directly to the underside of the joist, thus obviating the need for any additional supporting fixture. Unfortunately, however, more often than not it becomes necessary or desirable to mount a ceiling fixture at some point in a room in which the fixture will not register with a ceiling joist. The solution, therefore, has been to employ an adjustable or telescopic hanger bar, which is mounted to extend transversely in the space between a pair of adjacent ceiling joists.
By way of example, prior art hanger bars of the telescopic variety have been disclosed in U.S. Pat. Nos. 4,391,428, 3,518,421 and 3,425,655. Typically these bars comprise two, rigid, telescopically connected members having at opposite ends thereof sharp points or gripping surfaces. In use, the telescoped bar is inserted into the space between a pair of adjacent ceiling joists, and is then expanded to cause opposite ends thereof to be driven or otherwise secured to the confronting faces of the spaced ceiling joists, thus providing a stationary support that extends transversely, and generally horizontally, between the two joists. Thereafter the desired ceiling fixture is attached at its upper end through an opening in the ceiling to the hanger bar to be supported from the underside thereof.
One of the problems with prior such hanger bars has been the difficulty encountered in attempting to fix opposite ends of the bar to the confronting surfaces of a pair of spaced joists. It is essential, of course, that opposite ends of the bar be securely attached to the joists so that the bar will remain stationary after the ceiling fixture has been attached thereto. In the case of the above-described telescopic type hanger bar devices, it has been customary to employ a hammer or compression tool for driving the two telescopically connected parts away from each other in order to imbed or otherwise secure opposite ends of the bar to the adjacent joists.
U.S. Pat. Nos. 1,927,515 and 2,770,436, on the other hand, have disclosed hanger bars of the type comprising two, rigid members which are pivotally connected together, rather than being telescopically connected together. With these prior art devices the pivotally connected members are inserted in the space between a pair of adjacent joists while the two members are disposed in so-called collapsed positions in which they are inclined to each other. Then, in order to secure opposite ends of the bar to the two joists, the pivot point of the two members is shifted so that the members are swung almost into linear alignment with each other, thereby forcing opposite ends of the hanger bar away from each other, and in practice imbedding or otherwise securing opposite ends of the bar in the two joists.
While the above-described prior art hanger bars have been suitable for certain purposes, they each have certain disadvantages. In the case of the telescopic variety, the tool which is used to drive or otherwise force the two telescopically connected members away from each other must be sturdy and capable of imparting significant separating forces to the two members. In the case of the bars which comprise a pair of pivotally connected members, it heretofore has been extremely difficult to design the two members so that they can be adjustably connected to each other in order to accommodate the bar to different joist spacings, and yet also assure that the bar will be secured firmly in place when its two sections are swung into linear alignment with each other.
It is an object of this invention, therefore, to provide an improved hanger bar of the type described, which is a relatively simple and inexpensive to manufacture, and yet which can be readily and securely mounted between a pair of adjacent joists in the ceiling of a room, or the like.
More specifically, it is an object of this invention to provide an improved hanger bar of the pivotally connected variety, which can be readily adjusted to accommodate the bar for a variety of different joist spacings.
Other objects of the invention will be apparent hereinafter from the specification and from the recital of the appended claims, particularly when read in conjunction with the accompanying drawings.